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Figure 5: (a) Scanning electron micrograph of the γ-TiAl + 60 vol.% Ti5Si3 composite specimen showing that the two phases are very uniformly distributed in the microstructure. Such a microstructure is conducive to achieving superplastic deformation under appropriate conditions of testing. (b) Tensile stress-strain curve of γ-TiAl + 60 vol.% Ti5Si3 composite showing that superplastic deformation was achieved at 950°C with a strain rate of 4x10−5 s−1 and at 1000°C with a strain rate of 4x10−4 s−1.